There are 3 versions of the 242. If you have the 4.0 then you probably have the NV242J
If you have the 4.7 then you should have the stronger NV242HD (has a thicker chain and gears, same planar gears as the J though)
Then there is the one from the H1 and HMV. It doesn't have the 2wd option but has 6 planar gears vs 3 and the thicker chain and gears.

I've heard they can be swapped around and that they can't. I need to do more research as I want the NV242SHD that people have built where they combined the one from the HMV and the one from the jeep to give all shift options and vastly improved strength.

There are 3 versions of the 242. If you have the 4.0 then you probably have the NV242J

If you have the 4.7 then you should have the stronger NV242HD (has a thicker chain and gears, same planar gears as the J though)

Then there is the one from the H1 and HMV. It doesn't have the 2wd option but has 6 planar gears vs 3 and the thicker chain and gears.

I've heard they can be swapped around and that they can't. I need to do more research as I want the NV242SHD that people have built where they combined the one from the HMV and the one from the jeep to give all shift options and vastly improved strength.

I have a 4.0 so I guess I have an NV242J. Can it be upgraded or would I need to replace it?

Does the NV242HD from the 4.7 have all the shift options?

Is there source that sells the NV242SHD ready made?

Warning: I often edit my posts a few times to get them complete, or to correct errors.